1. Conservation of Energy

2. Forces Conservative Force - Gives back work done against it. (Gravity & springs) Non-conservative Force - Does not give back work done against it. (Friction) Criteria for a conservative force

3. Work on a Closed Path What total work is done by gravity going from A to B to C and back to A again? 0m -1m 1m A B C

4. Potential Energy If a force is conservative, it can be related to potential energy. For gravity near the earth’s surface

5. Falling Brick A 5.0 kg brick is tossed from a 14 m tall building. If the initial velocity were 20 m/s upward, what is the change in potential energy when the brick hits the ground? h

6. Millenium Force Are the predictions of the Millenium Force speed accurate? 300ft Drop >92mph

7. Mechanical Energy From the work energy theorem If only conservative forces working, then

8. Springs The potential energy in a spring is Ex. As a compound bow is drawn, it exerts a force of F=(  300x+150x 3 )N. What is the change in potential as it is drawn from x=0m to x=0.75m?

9. Arrow Speed What is the velocity of a 0.15 kg arrow fired by a composite bow with a force of F=(  300x+150x 3 )N and drawn to 0.75m?

10. Force and Potential If the potential is known, the force can be determined. Ex. The potential energy for a spring is given by the function U=5(2  x) 2 J. What is the spring constant for this spring?

11. Energy Sources Oil 38% Natural Gas 25% Nuclear 8% Coal 22%

12. Renewable Sources Solar Wind Hydroelectric

13. Energy & Well Being Basis of HDI –Longevity –Education –Standard of Living

14. Chemical Fuels Gas –Hydrogen (143 kJ/g) –Natural, Syngas (56 kJ/g) Liquid –Gasoline, Kerosene, heating oil (44 - 48 kJ/g) Solid –Coal (32 kJ/g) –Wood (10 – 19 kJ/g) –Stearic acid (40 kJ/g)

15. Einstein and Energy Relativity - Speed of Light is the same for everybody.Relativity - Speed of Light is the same for everybody. ConsequencesConsequences –Light bent by mass –Energy related to mass Ex. A nuclear power plant generates 300 GW of power. In one day how much mass is converted to energy?

16. Nuclear Power

17. Nuclear Fusion Nova Tokomak 1 gallon sea water = 300 gallon gasoline